Projectile motion

[Killjoy]

Can anyone help me with a formula that will allow me to input velocity and angle and hieght (if possible) and then move a shape along that path for the increase in time?

thanks

[A$$Bandit]

Yes you want to use the projectile motion curve formula:

y = height above horizontal
x = horizontal distance
A = angle of projection above horizontal
g = acceleration due to gravity (= 9.8ms^-2)
u = inital velocity

y = x.tanA - g.x².sec²A/2u²

Draw that out somehow, then just chuck in time 't' for horizontal range using s = ut. Use the displacement obtained to move your dot along the line or whatever.

[A$$Bandit]

Just in case this might help, the general projectile motion formula are:

1) GREATEST HEIGHT

h = u².sin²A / 2g

2) TIME OF FLIGHT

t = 2u.sinA / g

3) HORIZONTAL RANGE

R = u².sin2A / g

[Killjoy]

does anyone have like a program that works that uses this so i can like see how to do it.. im still kind of lost

[alkatran]

y = height above horizontal
x = horizontal distance
A = angle of projection above horizontal
g = acceleration due to gravity (= 9.8ms-2)
u = inital velocity

y = x.tanA - g.x2.sec2A/2u2

What are the '.' for? are they multiply?
TanA, do you mean tan(a)?
sec2a/2u2, do you mean sec(2a/2u2) and what does sec do

[kedaman]

a projectile travels in a straight line unless a net force accelerates it, the acceleration will be proportional to the force and reverse proportional to its mass, a=F/m

when accelerating the velocity of your projectile will change according to the formula a=dv/dt (acceleration is the time derivative of velocity) v=v0+a*t.
the displacement of your project will similarly be s=s0+v*t, the displacement as a function of acceleration would be after differentiation, s=v0*t+at/2, and as a function of force, s=v0*t+Ft/2m, however when dealing with gravity the mass and its effect due to the force will take out each other, and what you have left is called the gravitational constant, which is about 9.8m/s^2 at earth surface.

in two or more dimensions, you will have to treat displacement, velocity and acceleration as vectors, but the formulas are the same, to transform angles and scalar velocities into vectors, use the euler transformation: V(phi,r)=(r*cos(phi),r*sin(phi)) where r is your scalar velocity and phi your angle. you can use this n-1 times for n dimensions.

ugh, didnt really have time for a lengthy explanation but you could look up these stuff on google..

[SteveCRM]

excuse me if I read too quickly....but:

v=v0+a*t
should be
v=v0+a*(t^2)

[A$$Bandit]

Well you did read it too quickly, because under a constant acceleration, v = u + at.